CNMA: a European initiative for OSI network management

The authors describe the concepts, developments, and achievements of the ESPRIT project Communications Network for Manufacturing Applications in the field of OSI network management. Though being concentrated on LANs in manufacturing environments, the CNMA approach to OSI network management could be applicable to a wide variety of computer networks     

3-D reconstruction of 2-D crystals in real space

A new algorithm for three-dimensional reconstruction of two-dimensional crystals from projections is presented, and its applicability to biological macromolecules imaged using transmission electron microscopy (TEM) is investigated. Its main departures from the traditional approach is that it works in real space, rather than in Fourier space, and it is iterative. This has the advantage of making it convenient to introduce additional constraints (such as the support of the function to be reconstructed, which may be known from alternative measurements) and has the potential of more accurately modeling the TEM image formation process. Phantom experiments indicate the superiority of the new approach even without the introduction of constraints in addition to the projection data.     

Biological structure determination by EM is well suited to grid computing

Conclusion  This short note describes a potential application of grid computing in life sciences: high resolution structure determination of biological specimens by electron microscope tomography. It is shown there are excellent opportunities to benefit from grids: potential intensive applications to exploit the “high-throughput” and the “distributed supercomputing” capabilities of grids. Furthermore, grids may turn into reality solving problems not dared so far, such as structure determination of large viruses at near-atomic resolution or reconstruction of whole cells at molecular resolution. Grid computing will make it possible to afford those “grand challenge” applications currently unapproachable.     

The role of hysteroscopy in the diagnosis and follow-up of endometrial hyperplasia

BACKGROUND: Preneoplastic lesions of endometrium such as endometrial hyperplasia (simple and complex with or without cytological atypias) represent an important cause of abnormal uterine bleeding. Among diagnostic techniques, hysteroscopy presents several advantages: it is an out-patient procedure, minimally invasive, repeatable, of rapid execution and with low cost. The hysteroscopic pattern of endometrial hyperplasia appears with an over-development of the endometrial mucosa with increased glandular openings, increased vascularization, cystic dilatations, polypoid aspects. METHODS: Since October 1984 to January 1995 at the Gynecologic Endoscopic Service of Obstetrics and Gynecology Department of the University of Bologna, 13,438 hysteroscopies were performed: 291 (2.16%) in patients submitted to hysteroscopy for previous diagnosis of endometrial hyperplasia. The first diagnosis of endometrial hyperplasia was made in 125 (42.3%) patients through hysteroscopic biopsy, while for 166 patients (57.04%) the first diagnosis was made by endometrial curettage of VABRA. RESULTS: The results showed that the endometrial hyperplasia is typical in perimenopausal age and this finding is more frequently symptomatic. The histological diagnosis after hysteroscopy was: simple hyperplasia in 106 patients (84.8%), complex in 12 patients (9.6%) and atypical in 6 patients (4.8%). One case of simplex hyperplasia was associated with endometrial cancer (0.8%). The comparison between histological diagnosis and hysteroscopic diagnosis showed that agreement is reached in 113 cases (90.4%). However, it is to note that diagnostic agreement of complex hyperplasia cases was about 100%, but in 22 cases the hysteroscopic diagnosis was simplex hyperplasia rather than complex or atypical. The errors of hysteroscopy were observed in 10 cases (8%). CONCLUSIONS: The hysteroscopic diagnosis should not replace histological diagnosis, mostly in hysteroscopies performed after progestagen therapy, because the changes induced by drugs make more difficult the interpretation of hysteroscopy. However, hysteroscopy is complementary to histological analysis since permits a global evaluation of endometrial mucosa, directs biopsy on dishomogeneous areas and represents the only means to make diagnosis when biopsy is not practicable.     

Is normal bronchial responsiveness in asthmatics a reliable index for withdrawing inhaled corticosteroid treatment?

STUDY OBJECTIVE: Inhaled corticosteroid (ICS) treatment is first-line maintenance therapy in bronchial asthma. However, it is not clear whether and when ICS treatment can be withdrawn. The aim of this open study was to assess whether normalization of bronchial responsiveness could be used as a reliable index to assess the opportunity of ICS treatment withdrawal. DESIGN: Open study at two different points in time. SETTING: Outpatient pulmonary clinic. PATIENTS: Eighteen asthmatic subjects. MEASUREMENTS AND RESULTS: ICS therapy was withdrawn in subjects treated with beclomethasone dipropionate, at the maintenance dose of 889+/-246 microg/d for >3 months. Upon recruitment, all subjects were asymptomatic, had FEV1 >70% of predicted value, and were in treatment with beta2-agonists on an as-needed basis. Eight subjects (group 1) had normal bronchial responsiveness (methacholine provocative dose causing a 20% fall in FEV1 [PD20] >2,000 microg) and 10 subjects (group 2) had bronchial hyperresponsiveness (BHR) (PD20 < or = 2,000 microg). After withdrawal of ICS treatment, subjects were followed up for 3 weeks and were asked to record their asthma symptoms (cough, dyspnea, and wheezing) and their beta2-agonist use. At recruitment and at the end of follow-up, subjects underwent spirometry and a methacholine challenge test. Frequency of asthma exacerbation was similar in subjects with normal bronchial responsiveness (NBR) and in subjects with BHR (50% vs 60%), but subjects with NBR tended to remain asymptomatic for longer than those with BHR (mean+/-SD, 10.7+/-4.4 days vs 5.5+/-3.8 days) (p=0.08). None of the subjects reported any condition that could have triggered exacerbation. Asthma exacerbation was associated with a significant decrease in FEV1 (-105+/-107 mL; p<0.05) and in PD20 (-1,332+/-1,020 microg; p<0.001). CONCLUSIONS: Our study shows that the likelihood of asthma exacerbation is not reduced if ICS treatment is withdrawn when the subjects have NBR, but the exacerbation could be delayed. Further studies in larger populations of asthmatics are needed to confirm these findings.     

EFFECT OF CLAY CONTENT ON SURFACE CHARACTERISTICS OF COAL GROUND UNDER DIFFERENT CONDITIONS

The surface characteristics of a coal with a kaol in content of 7% have been studied.

The coal has been either wet or dry ground, with and without an additive. All the products have been examined by XPS and IR spectrometry.

The results show that the wet and dry grinding lead to different surface content of the clay species, while the additive seems to have negligible effect. Wet grinding leads to a concentration of kaolin on the coal surface that is 3 times higher than in the case of the dry ground sample and 7 times higher than in the bulk.     

SYNTHETIC COPOLYMERS CONTAINING FREE OR PROTECTED CATECHOL RESIDUES FOR THE pH-CONTROLLED SELECTIVE FLOCCULATION OF ULTRAFINE DISPERSIONS OF ILMENITE WITH RESPECT TO RUTILE

Several multifunctional polymers for the pH controlled flocculation of titanium minerals active towards ilmenite and selective respect to rutile have been prepared. They are radical vinyl copolymers containing catechol functions either free or protected and acrylic acid units. They show the distinctive property of changing their effect from flocculating to dispersing or inert and vice versa by changing pH, with great advantages for the best fulfilment of the flocculating process. The tendency of the ilmenite particles to gather, as a result of the combined effect of the cathecholic and carboxylic functions at acidic pH, is considered an essential conditions and a preliminary process for the formation of floes     

Ploidy disturbances as an early indicator of intrinsic malignancy in endometrial carcinoma

Ursodeoxycholic acid is an efficient treatment for putatively immune-mediated liver diseases, but its mechanism of action is unknown. We studied human mononuclear cell proliferation as an in vitro model for cell-mediated immunity in the presence of ursodeoxycholic acid, its glycoconjugate and tauroconjugate and chenodeoxycholic acid at concentrations of 5, 25 and 50 mumol/L. Proliferation was inhibited in a dose-dependent manner compared with control values (15% to 54% depending on the bile acid, concentration and mitogen used), except at 5 mumol/L where inhibition was significant with only one mitogenic stimulus of the three used. With one mitogen (phorbolester) the inhibition was additive with that of cyclosporine. The number of cell-surface receptors studied was not modified by bile acids. Interleukin-2 production was decreased 35% to 60% by ursodeoxycholic acid and its conjugates. The proliferation of the interleukin-2-dependent cell line CTLL-2 was also inhibited. The immunosuppression was reversible except at a chenodeoxycholic acid concentration of 50 mumol/L. Because bile acids are able to partition into membranes and change their properties, we speculate that this allows them to interact with cell-surface receptors or signaling systems within the membrane or on its inner face, thus impairing their function. This would inhibit the numerous extracellular messages that lymphocytes need to proliferate.     

Toxicity evaluation of surface water treated with different disinfectants in HepG2 cells

It is well known that water disinfection through chlorination causes the formation of a mixture of disinfection by-products (DBPs), many of which are genotoxic and carcinogenic. To demonstrate the formation of such compounds, a pilot water plant supplied with water from Lake Trasimeno was set up at the waterworks of Castiglione del Lago (PG, Italy). The disinfectants, continuously added to pre-filtered lake water flowing into three different basins, were sodium hypochlorite, chlorine dioxide and peracetic acid, an alternative disinfectant used until now for disinfecting waste waters, but not yet studied for a possible use in drinking water treatment. The aim of this study was to evaluate the formation during the disinfection processes of some toxic compounds that could explain the genotoxic effects of drinking waters. Differently treated waters were concentrated by solid-phase adsorption on silica C(18) columns and toxicity was assessed in a line of human hepatoma cells (HepG2), a metabolically competent cellular line very useful for human risk evaluation. The seasonal variability of the physical-chemical water characteristics (AOX, UV 254 nm, potential formation of THM, pH and temperature) made indispensable experimentation with water samples taken during the various seasons. Autumn waters cause greater toxicity compared to those of other seasons, in particular dilution of the concentrate at 0.5l equivalent of disinfected waters with chlorine dioxide and peracetic acid causes a 55% reduction in cellular vitality while the cellular vitality is over 80% with the all other water concentrates. Moreover it is very interesting underline that non-cytotoxic quantities of the autumnal water concentrates cause, after 2h treatment, a decrease in GSH and a statistically significant increase in oxygen radicals, while after prolonged treatment (24h) cause a GSH increase, without variations in the oxygen radical content. This phenomenon could be interpreted as the cellular adaptation response to an initial oxidative stress.